Abstract:

An apparatus for rotation of a structural beam during fabrication thereof
comprises spaced mounting members, each mounting member including a base
frame and a circular support bracket supported for rotation by spaced
rollers mounted on said base frame. At least one of the spaced rollers
includes a drive mechanism to rotate the support brackets with a beam
located therein. Each support bracket comprises a beam clamp mechanism
with a stationary portion and a movable portion pivotably mounted thereto
to form opposable jaws to receivably locate said beam therein.

Claims:

1. An apparatus for selective rotation of an elongate member about a
longitudinal axis, said apparatus comprising: spaced mounting members,
each mounting member including a base frame and a circular support
bracket supported for rotation by spaced rollers mounted on said base
frame, at least one of said mounting members including a drive mechanism
for at least one of said spaced rollers, each said circular support
bracket including an adjustable mount to support said elongate member
adjacent a respective end thereof during rotation of said elongate member
about a longitudinal axis thereof.

2. An apparatus as claimed in claim 1 wherein one of said mounting members
is movable relative to another of said mounting members.

3. An apparatus as claimed in claim 1 wherein one of said mounting members
is mounted on a track for movement relative to another of said mounting
members.

4. An apparatus as claimed in claim 1 wherein at least one of said spaced
rollers associated with each base frame is driven for selective rotation
of a circular support bracket.

5. An apparatus as claimed claim 1 wherein each of said spaced rollers
includes a drive mechanism for selective rotation of a respective
circular support bracket.

6. An apparatus as claimed in claim 5 wherein respective drive mechanisms
of each driven roller are coupled for selective rotation about a
longitudinal axis of an elongate member supported between said spaced
mounting members.

7. An apparatus as claimed in claim 1 wherein a circumferential edge of
said circular support bracket and/or a circumferential contact surface of
a respective driven roller are contoured for driving engagement
therebetween.

8. An apparatus as claimed in claim 1 wherein said circular support
bracket includes an adjustable clamp mechanism to clamp an elongate
member intermediate its ends.

9. An apparatus as claimed in claim 8 wherein said adjustable clamp
mechanism includes opposable jaw members comprising a respective static
portion of said circular support bracket and a movable portion of said
support bracket pivotably coupled to said static portion.

10. An apparatus as claimed in claim 9 wherein said adjustable clamp
mechanism includes a locking mechanism to lock together respective free
ends of said static portion and said movable portion of said circular
support bracket during rotation thereof.

11. An apparatus as claimed in claim 10 wherein locking mechanisms are
positioned adjacent opposed ends of said static and movable portions to
allow selective opening of said claim mechanism from either end thereof.

12. An apparatus as claimed in claim 11 wherein said locking mechanisms
are engageable with respective pivot couplings pivotably mounted on said
support bracket adjacent respective said locking mechanisms.

13. An apparatus as claimed in claim 9 wherein said opposable jaw members
together define a shaped jaw opening located generally centrally of said
circular support bracket.

14. An apparatus as claimed in claim 13 wherein said shaped jaw opening
has a rectangular configuration.

15. An apparatus as claimed in claim 13 wherein said adjustable clamp
mechanism includes lip members releasably securable to said jaw members,
said lip members, together defining a shaped jaw aperture corresponding
to a cross-sectional region of an elongate member clamped therein.

16. An apparatus as claimed in claim 9 wherein each said mounting member
includes at least one actuating mechanism to selectively move said
movable portion of said circular support bracket between a closed
position and an open position about a pivotable coupling therebetween.

17. An apparatus as claimed in claim 16 wherein each said mounting member
includes opposed actuating mechanisms to selectively move said movable
portion between a closed position and an open position about a pivotable
coupling at one side or an opposite side of said mounting member to
permit location of said elongate member therein.

18. A method of rotating an elongate member about a longitudinal axis
thereof, said method including the steps of: mounting an elongate member
to circular support brackets of respective spaced mounting members, each
said circular support bracket being rotatably supported on spaced
rollers; and, actuating a drive mechanism associated with at least one of
said spaced rollers to effect rotation of said circular support brackets.

19. A method as claimed in claim 18 wherein said elongate member is
mounted in a jaw opening defined between a stationary portion and a
movable portion of said circular support bracket, said movable portion
being pivotally coupled adjacent one end thereof to said stationary
portion.

20. A method as claimed in claim 19 wherein lip members are releasably
secured to jaw members defining said jaw opening, said lip members
together defining a jaw aperture corresponding to a cross sectional
region of an elongate member secured therewithin.

Description:

FIELD OF THE INVENTION

[0001]This invention is concerned with an apparatus for manipulation of
structural members to assist in the fabrication thereof.

[0002]The invention is concerned particularly although not exclusively
with an apparatus and method for rotation of a structural beam about a
longitudinal axis during fabrication.

BACKGROUND OF THE INVENTION

[0003]In the fabrication of large steel structural members such as portal
frames, roof trusses and structural beams, various elements including
webs and flanges are secured by manual or automated welding processes.
Typically, the web and flange elements are arranged in a predetermined
juxtaposition on a surface or a purpose built support jig to facilitate
joining of the various elements, usually by a fillet welding process.

[0004]Initially, the web may be supported horizontally with the flange
elements positioned in an upright manner against the edges of the web. In
some cases, reinforcing braces or flange support members extend across
the face surface of the web between adjacent flanges thus presenting both
horizontal and vertical weld tracks. Because of the size of the weld
bead(s) to be deposited manually or otherwise due to limitations in
automated welding apparatus, most weld beads are laid in a horizontal
position.

[0005]Accordingly, in the fabrication of a structural beam with a web,
main flanges, web reinforcing ribs, mounting brackets and the like, it is
necessary to rotate the beam at least through four 90° quadrants
during the fabrication process in order to present horizontally oriented
weld bead positions. Typically, rotation of the beam during the
fabrication process is effected by a gantry crane supporting the beam
while balanced in a loose sling such that as the beam is elevated above
the jig or support base, it is able to rotate under the influence of
gravity through at least 45° whereby when lowered by the crane
back onto the jig or support base, it completes a 90° quadrant
rotation to present a series of horizontal weld bead positions on each
side of the now upright web. This process is repeated three times to
effect welding of all joints with horizontally laid weld beads.

[0006]While generally effective for its intended purpose, the use of a
gantry crane is quite inefficient in terms of labour intensity and the
need for fabrication jigs to be located longitudinally under the travel
shadow of the gantry crane.

[0007]Moreover, the requirement to balance such beams in a support sling
during rotation about a longitudinal axis is a quite dangerous procedure,
particularly for tapered beams necessitating a non-central location of
the supporting sling. A further disadvantage of this handling method is
that a separate sling is required for differing beam sizes and
configurations.

[0008]Various mechanisms for rotation of large objects about a horizontal
axis are known. For example, U.S. Pat. Nos. 4,053,365, 5,437,707 and
6,860,735 all describe rotary kilns comprising an inclined cylinder
supported for rotation by idler rollers engaging a circumferential track.
The cylindrical kilns may be driven by a toothed pinion engaging in a
toothed circumferential rack extending about the cylinder, a chain and
sprocket drive, etc. While generally effective for their intended
purpose, they require special thrust bearings to support the load of the
inclined cylinder and otherwise are only suited to driving elongate
cylindrical members.

[0009]An alternative mechanism for rotation of large objects about a
longitudinal axis comprises a powered sling mechanism supportable from a
gantry crane hook. The sling may be an endless loop of chain or cable and
is powered by a drive motor remotely actuable by an operator. Again, this
system does not really avoid the shortcomings and safety issues
associated with the rotation about a longitudinal axis of large objects
such as structural members whilst suspended by a gantry crane or the
like.

[0010]Accordingly, it is an object of the invention to overcome or
alleviate at least some of the disadvantages associated with prior art
methods and apparatus for rotating large structural members about a
longitudinal axis and otherwise provide steel fabricators and the like
with a convenient choice.

SUMMARY OF THE INVENTION

[0011]According to one aspect of the invention there is provided an
apparatus for selective rotation of an elongate member about a
longitudinal axis, said apparatus comprising:

[0012]spaced mounting members, each mounting member including a base frame
and a circular support bracket supported for rotation by spaced rollers
mounted on said base frame, at least one of said mounting members
including a drive mechanism for at least one of said spaced rollers, each
said circular support bracket including an adjustable mount to support
said elongate member adjacent a respective end thereof during rotation of
said elongate member about a longitudinal axis thereof.

[0013]If required, one of said mounting members may be movable relative to
another of said mounting members.

[0014]Suitably, one of said mounting members may be mounted on a track for
movement relative to another of said mounting members.

[0015]At least one of said spaced rollers associated with each base frame
may be driven for selective rotation of a circular support bracket.

[0016]Preferably, each of said spaced rollers includes a drive mechanism
for selective rotation of a respective circular support bracket.

[0017]Suitably, respective drive mechanisms of each driven roller are
coupled for selective rotation about a longitudinal axis of an elongate
member supported between said spaced mounting members.

[0018]If required, a circumferential edge of said circular support bracket
and/or a circumferential contact surface of a respective driven roller
may be contoured for driving engagement therebetween.

[0019]Suitably, said circular support bracket includes an adjustable clamp
mechanism to clamp an elongate member intermediate its ends.

[0020]The adjustable clamp mechanism may include opposable jaw members
comprising a respective static portion of said circular support bracket
and a movable portion of said support bracket pivotably coupled to said
static portion.

[0021]If required, said adjustable clamp mechanism may include a locking
mechanism, to lock together respective free ends of said static portion
and said movable portion of said circular support bracket during rotation
thereof.

[0022]Suitably locking mechanisms are positioned adjacent opposed ends of
said static and movable portions to allow selective opening of said clamp
mechanism from either end thereof.

[0023]Preferably the locking mechanisms are engagable with respective
pivot couplings mounted on said support bracket adjacent respective said
locking mechanisms.

[0024]Suitably, said opposable jaw members together define a shaped jaw
opening located generally centrally of said circular support bracket.

[0025]Preferably, said shaped jaw opening has a rectangular configuration.

[0026]If required, said adjustable clamp mechanism may include lip members
releasably securable to said jaw members, said lip members, in use,
together defining a shaped jaw aperture corresponding to a
cross-sectional region of an elongate member clamped therein.

[0027]Preferably, each said mounting member includes at least one
actuating mechanism to selectively move said movable portion of said
circular support bracket between a closed position and an open position
about a pivotable coupling therebetween.

[0028]According to another aspect of the invention there is provided a
method of rotating an elongate member about a longitudinal axis thereof,
said method including the steps of:

[0029]mounting an elongate member to circular support brackets of
respective spaced mounting members, each said circular support bracket
being rotatably supported on spaced rollers; and,

[0030]actuating a drive mechanism associated with at least one of said
spaced rollers to effect rotation of said circular support brackets.

[0031]Suitably each said mounting member includes opposed actuating
mechanisms to selectively move said movable portion between a closed
position and an open position about a pivotable coupling at one side or
an opposite side of said mounting member to permit location of said
elongate member therein.

[0032]If required said elongate member may be mounted in a jaw opening
defined between a stationary portion and a movable portion of said
circular support bracket, said movable portion being pivotably coupled
adjacent one end thereof to said stationary portion.

[0033]Preferably lip members are releasably secured to jaw members
together defining said jaw opening, said lip members together defining a
jaw aperture corresponding to a cross sectional region of an elongate
member secured therewithin.

[0034]Throughout this specification and claims which follow, unless the
context requires otherwise, the word "comprise", and variations such as
"comprises" or "comprising", will be understood to imply the inclusion of
a stated integer or group of integers or steps but not the exclusion of
any other integer or group of integers.

BRIEF DESCRIPTION OF THE DRAWINGS

[0035]In order that the aspects of the invention may be fully understood
and put into practical effect, a preferred embodiment will now be
described with reference to the accompanying drawings in which:

[0038]FIG. 3 shows an alternative embodiment of the mounting member of
FIG. 2;

[0039]FIG. 4 shows a side elevational view of the embodiment of FIG. 3;
and

[0040]FIG. 5 is a schematic plan view of portion of a beam assembly line
incorporating a pair of mounting members according to the invention.

[0041]In the drawings, like numerals have been employed for like features
for the sake of clarity.

DETAILED DESCRIPTION OF THE DRAWINGS

[0042]An apparatus for selective rotation of an elongate member such as a
structural beam comprises a pair of mounting members 1 spaced apart along
a rotational axis of respective circular support brackets 2.

[0043]Each mounting member 1 includes a base frame 3 with support rollers
(not shown) rotatably mounted thereon to rotatably support a circular
support bracket 2. A drive motor 4 such as a stepping motor or the like
may be coupled to a roller via a drive shaft 5. An upright post 6 on each
side of base frame 3 includes a guide mechanism 7 in the form of
journalled rollers (not shown) which engage opposite faces of circular
support bracket 2 adjacent an outer perimeter thereof to support bracket
2 during rotation.

[0044]Circular support bracket 2 is comprised of a first jaw portion 8
pivotably mounted to a second jaw portion 9 via a pivot coupling 10.
Opposite pivot coupling 10 is a lock mechanism 11 (partly shown) to lock
the first and second portions 8,9 together during rotation of circular
support bracket 2. Pivotably coupled portions 8,9 together define a
rectangular jaw aperture 12 therebetween and a plurality of spaced
apertures 13 are adapted to removably mount lip members 17 via aligned
apertures 13,13a to define jaw apertures 12 of differing shapes and
sizes, the purpose of which will be described later.

[0046]In FIG. 2, the apparatus is shown with first and second jaw portions
8,9 in an open position. To open jaw members 8,9, a locking pin (not
shown) engaging aligned apertures 17 of lock mechanism 11 and second jaw
member 9 is removed when the second jaw edge 9a is in a horizontal
position. In this position, opposable clamps 15 are initially engaged
with an adjacent aperture 14 in first jaw portion 8 and jaw opening
mechanism 16 is actuated to retract clamps 15 causing first jaw member 8
to pivot to the open position as shown.

[0047]In the open position shown, an elongate beam or the like having a
cross-sectional shape corresponding to jaw aperture 12 may be positioned
on spaced second jaw edges 9a by a gantry crane, mobile crane, fork lift
or the like. Jaw opening mechanism 16 is then actuated to close first jaw
member 8 relative to second jaw member 9 and clamps 15 are disengaged. A
locking pin (not shown) is then inserted into aligned apertures 17 in
lock mechanism 11 and second jaw member 9 to securely locate the beam
(not shown) therein.

[0048]Suitably, all four drive mechanisms 4 of the spaced mounting members
are electrically coupled such that circular support brackets 2 rotate in
unison when drive mechanism 4 is actuated. It readily will be apparent to
a skilled addressee that a tight clamping engagement is not necessary
between the jaw members 8 and 9 and a beam positioned therebetween as the
beam can safely move to a limited degree in the plane of rotation of
circular support member 2 as support member 2 rotates relatively slowly
as to avoid high impact loads between itself and the beam.

[0049]The apparatus according to the invention is adaptable to elongate
members having a wide range of cross-sectional shapes and sizes by simple
interchange of lip members 17 securable to jaw members 8,9 by securing
pins or bolts (not shown) via apertures 13.13a. For example, a typical
portal frame beam comprises a tapered web and flange structure which may
have a width at one end of up to 1200 mm and a width at its opposite end
of 300 mm with a constant flange width of say 250-300 mm.

[0050]Interchangeable lip members 17 allow ready adaptation of the jaw
members 8,9 to elongate members wherein dimensions and/or shape change
from one end to the other. For example, as shown in FIG. 1, lip members
17 can be adjusted transversely by locating the securing pins or bolts
(not shown) in aligned selected mounting apertures 13,13a. For beams
having a thickness less than the notched jaw 19 of lip members 17,
interchangeable lip members having differing jaw apertures may be
employed. Where lip members 17 are employed, a beam is first located on
second jaw edges 9a and the jaw opening mechanism is actuated to close
jaw member 8. With a first lip member 17 secured in place, the beam is
then lifted into place in the notched jaw aperture 19 of lip member 17
while a second lip member is secured to support bracket 2. The crane than
is no longer required until the finished beam is to be removed from the
apparatus.

[0051]FIG. 3 shows an alternative embodiment of the apparatus of FIGS. 1
and 2.

[0052]On FIG. 3 the apparatus comprises a pair of spaced circular support
brackets 2, 2a coupled by connecting pins 20 but otherwise substantially
identical to the circular support bracket shown in FIGS. 1 and 2.

[0053]First jaw portion 8 of bracket 2 comprises a pair of apertured pivot
couplings 10 at each inner end thereof, the pivot couplings being
pivotally mounted on upper jaw portions by link pins 10a. When jaw
portions 8, 9 are closed, apertures 21 in the free ends of couplings 10
are aligned with retractable locking pins 22 of locking mechanisms 23
located in opposite ends of lower jaw portion 9 to selectively lock upper
and lower jaw portions 8, 9 together. Locking mechanisms 23 may comprise
a pneumatic, hydraulic or electromechanical mechanism coupled to
rotatable coupling 24 for connection to a source of compressed air,
pressurized hydraulic fluid or a source of electric power as appropriate.

[0054]The combination of pivot couplings 10 and locking mechanisms 23
allows the jaw portions 8, 9 to be selectively opened from either side of
circular support bracket 2 with a pivotable connection being maintained
at an opposite side of bracket 2. In the embodiment shown jaw opening
mechanisms 16 are provided on opposite sides of the apparatus for
selective opening of jaw members 8, 9 from one side or the other of
support bracket 2, the purpose of which selective opening function will
be described later.

[0055]It will also be noted that by simultaneous retraction of both
locking pins 22, the upper jaw portion 8 may be removed from the
apparatus for any purpose such as maintenance or the like. If required,
jaw opening mechanisms 16 may be mounted on support posts 25 in turn
pivotally mounted on opposed posts 6 of base frame 3 or otherwise
telescopically extendible to an extended position shown from a retracted
position (not shown) below jaw edges 9a to facilitate loading of a beam
into the apparatus from a conveyor system (not shown).

[0056]The structure illustrated in FIG. 3 provides a more robust structure
that that illustrated in FIGS. 1 and 2 and is thus better suited to
handling of larger structural beams or the like.

[0057]FIG. 4 shows a partial side elevational view of the apparatus
illustrated in FIG. 3.

[0058]In FIG. 4, a structural beam 30 is shown clamped within lip members
17 secured to opposed circular support brackets 2, 2a by removable
locating pins 31. Although a pair of opposed lip members 17, 17a is
shown, it should be understood that a single pair of lip members 17 may
be employed on either of support brackets 2, 2a.

[0059]FIG. 4 shows more clearly the locking mechanism 23 located between
opposed circular support brackets 2, 2a with retractable locking pins 22
located in aligned apertures in pivot couplings 10. Rotatable coupling 24
enables rotation of circular support brackets being coupled by a conduit
or cable 32 to a source 33 of compressed air, pressurized hydraulic fluid
or electric power as appropriate.

[0060]The circular support bracket assembly 2, 2a may be supported for
rotation on a shouldered roller assembly depicted by roll portion 34 or
alternatively a roller combination depicted by roll portions 35, 36
wherein upper shouldered roller 35 engages over a peripheral rim 37 for
further stability of the beam rotation apparatus.

[0061]FIG. 5 shows schematically portion of an assembly line for
fabricated structural beams.

[0062]A jig mounted beam assembly or tack welded beam assembly 30 is
advanced on a conveyor system 40 towards spaced mounting members 1, 1a
with jaw opening mechanisms 16 in a retracted state and jaw locking
mechanisms 23 disengaged while opposed jaw locking mechanisms 23a are
maintained in an engaged state. Jaw opening mechanisms 16a are then
actuated to open upper jaw portions 8 to receive advancing beam assembly
30. When the beam is positioned between jaw portions 8, 9, jaw opening
mechanisms 16a are actuated to close jaw portions 8, 9 prior to actuating
jaw locking mechanisms 23. If required, appropriately shaped lip members
(not shown) can then be secured to jaw portions 8, 9 to securely locate
the beam assembly within the spaced mounting members 1, 1a.

[0063]An automated or robotic welding apparatus (not shown) may then be
activated to perform required welding processes between the web 30a,
flanges 36b and ribs 30c of beam assembly 30 before mounting members 1,
1a are rotated in unison through 90° steps as required for a
typical automated welding sequence. As shown in FIG. 5, the beam assembly
30 mounted in spaced mounting members 1, 1a has been rotated through
180° from its initial loading position. When the welding cycle is
completed, the spaced mounting members 1, 1a will have rotated through
360° whereupon jaw opening mechanisms 16a are retracted, jaw
locking mechanisms 23a deactivated and then jaw opening mechanisms 16 are
actuated to open upper jaw portions 8. The completed beam 41 is then
conveyed from the mounting members 1, 1a by a further conveyor system 42
to a finishing station or the like for a final finishing and inspection
operation prior to shipping.

[0064]To accommodate beams of differing lengths, one of the mounting
member base frames 3 may be fixedly secured to a support base and the
other base frame may be movable relative thereto. The movable base frame
may be movable between spaced mounting locations on a support base or it
may be mounted on a track 43. Alternatively, both base frames 3 may be
mounted on a track for relative movement therebetween.

[0065]Again it readily will be apparent to a skilled addressee that the
present invention provides a simple and elegant, yet safe alternative for
rotation about a longitudinal axis of elongate members such as structural
beams or the like during fabrication thereof.

[0066]Many modifications or adaptations may be made to the preferred
embodiments without departing from the spirit and scope of the invention.